What would cause this to only run when putting gas in the intake

If the fuel injectors are good what would cause the connectors to not pulsate we took it to auto zone and they said 2 and 4 had low circuits so we changed them spark plugs and it still wont run at all we had to spray gas in the intake to keep it running as soon as you stop sprayin it in there it stops running

Fuel pump is faulty or clogged line, you will see a hose on the lhs of engine going into the fuel filter, at the top will be printed TANK pull that hose out and crank engine, any fuel coming out?And at what rate between 0-5%?Or firstly turn the key to on position NOT cranking and listen for fuel pump priming, you'll hear a grinding noise yeah?